Multiple battery cells configured as a battery pack by serially connecting a positive electrode of one of the battery cells and a negative electrode of another battery by a busbar is known as a battery installed on an electric vehicle and a hybrid vehicle (refer to a Patent Document 1, for example). Such a battery pack is characterized by a high output and a high energy density, and lithium ion batteries are used as the battery cells in most cases. The lithium ion battery has a plus output terminal formed by aluminum (Al) as a raw material, and a minus output terminal formed by copper (Cu) as a raw material.
There is a busbar (component for distribution of electric energy) as a component for connecting the terminals of the battery cells with each other. There is a manufacture of laser-welding members constructing busbars to each other as a method for producing the busbar as disclosed in “Technical Problem” of the Patent Document 2.